package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import javax.annotation.Resource;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {

    private static final long BEGIN_TIME = 1640995200L;

    //序列号位数
    private static final int COUNT_BITS = 32;

    @Resource
    private StringRedisTemplate stringRedisTemplate;

    public Long nextId(String keyPrefix) {

        //1.生成时间戳
        LocalDateTime now = LocalDateTime.now();
        //当前秒数
        long nowSecond = now.toEpochSecond(ZoneOffset.UTC);

        long timeStamp = nowSecond - BEGIN_TIME;

        //2.生成序号 key统计当天销售量
        String date = now.format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));

        //icr:order:2025:06:16 = 0 , 1
        //icr:order:2025:06:17 = 0 第二天会重新计数
        long count = stringRedisTemplate.opsForValue().increment("icr:" + keyPrefix + ":" + date);


        //3.拼接返回

        return timeStamp << COUNT_BITS | count;

    }


}
